Seasonal Variations in Serum 25-hydroxy Vitamin-D Levels in a Swedish Cohort

Completed

• Conditions: Vitamin-D Insufficiency

• Registration Number: NCT02136407
• Lead Sponsor: Sahlgrenska University Hospital, Sweden

Brief Summary

The purpose of this study was to study seasonal inter-individual and intra-individual variations in S-25(OH)D and to explore parameters associated with S-25-OHD in healthy Swedish adults.

Detailed Description

Serum was collected during 12 months and analysed for 25(OH)D in 540 healthy blood donors. The blood donors answered questionnaires concerning vitamin D supplements, smoking, physical activity, sunbed use and holidays in sunny locations. Repeated serum samples were also collected from thrombocyte donors to study the intra-individual variations in S-25(OH)D.

Study Timeline

• Study Start: 2009-10
• Primary Completion: 2010-09
• Study Completion: 2010-09
• Status Verified: 2014-05
• Study First Submitted: 2014-05-02
• Study First Submitted QC: 2014-05-12
• Last Update Submitted: 2014-05-12
• Study First Posted: 2014-05-13
• Last Update Posted: 2014-05-13

Recruitment & Eligibility

• Status: COMPLETED
• Sex: All
• Target Recruitment: 615

Inclusion Criteria

• healthy at the time of donating blood

Exclusion Criteria

• unhealthy

Study & Design

• Study Type: OBSERVATIONAL
• Study Design: Not specified

Primary Outcome Measures

Name	Time	Method
Inter-individual and intra-individual varations in serum 25-hydroxy vitamin-D during different seasons.	Group1:Blood donors, single test, 25(OH)vit D at inclusion . Group 2: thrombocyte donors: multiple tests, serum 25(OH)vit D during 8 months.

Trial Locations

Locations (1)

Sahlgrenska University Hospital; 🇸🇪 Gothenburg, Sweden